Gamma-Ray Lens May Allow for New Optical SystemsCategory: Science & Technology
Posted: May 10, 2012 12:11PM
As the electromagnetic spectrum stretches from radio waves to gamma rays, energy increases and wavelength decreases. X-rays, a step before gamma rays, have such a small wavelength that only the electrons in a crystal lattice are able to affect them. Researchers believe that gamma rays, with even shorter wavelengths, cannot be affected even by these electrons, but new evidence is challenging that idea.
Researchers shot two identical gamma ray beams into a spectrometer, with one beam going directly to the device while the other had to pass through a silicon prism first. Astonishingly, the researchers were able to measure a very small, but definite deflection caused by the prism. At just one millionth of a degree, the effect is too small to be of much use, but this shows it is possible to deflect gamma rays, so it may be possible to create new kinds of gamma ray optics.
The researchers are not entirely sure how the gamma rays were deflected, but they have an idea. Photons are deflected when they interact with electrons. The electrons in the outer shell of an atom may not be able to affect gamma ray photons much, but virtual electrons in the nucleus may amplify the photon scattering. One consequence of quantum mechanics is that particles, and their corresponding antiparticles, can spontaneously form within the nucleus of an atom. The researchers believe these virtual particles that pop in and out of existence are responsible for the deflection.
As gamma ray deflection is studied and becomes better understood, it may be possible to create advanced gamma ray detection systems for medical purposes and a way to make nuclear waste nonradioactive. Different materials, with larger or smaller nuclei, will affect gamma rays differently. Doctors could be able to identify radioactive tracer chemicals injected in a body. The interaction between gamma rays and the nuclei of atoms could allow for nuclear reactions that stabilize the materials in nuclear waste.